Modem installation

6. Modem installation

6.1. General description of installation

Racom routers are built into a robust metal case and are suitable for
applications which place them in various environments from air-conditioned
offices to heavy industry factories. To a certain extent the method of
installation needs to be adapted to this. All information in this chapter
describes the standard method of installation for normal industrial
applications, which has been derived from valid regulations for such
equipment and also from the long-term experience of our engineers. In the
case of larger-scale networks and more complicated applications we recommend
that users order a project assessment from Racom, or a partner company,
which should consist of careful measurements of the strength and quality of
a signal and an assessment of the conditions for the propagation of radio
waves.

Each radio equipment must comply with operating
conditions for the given frequency band in the country in which it is
operated and the person running the equipment is responsible for
this.

For reliable operation of routers it is important to
ensure that all equipment, for which data is transmitted through the router,
is connected correctly. Also ensure the antenna is correctly connected and
installed, a suitable and safe supply of electricity is provided, equipment
is mounted correctly, and that all corresponds to the given operating
conditions, without a negative influence on the specific properties of our
equipment. A description and wiring of individual connectors and
interfaces is described in the connectors
chapter.

Fig. 6.1: Example of a typical installation of a data network radio
point

6.2. Antenna installation

Optimum installation of the antenna is influenced by a number of
factors. The topology of the radio network, the separation of radio points,
the terrain profile between them, and conditions for signal propagation all
influence the type of antenna to be used and where it should be located.
Sometimes the appearance of the structure on which the antenna is to be
located and the possibility of its damage in publicly accessible places
should also be taken into consideration. Generally it can be said that for
point-to-point type connections directional antennas are used, and for more
remote points and points with a poorer signal multilink directional antennas
with greater gain are used. The height of the antenna above ground level may
improve the quality of the signal. The standard height of approx. 5 m can be
increased severalfold, but always in consideration of the length of the
antenna lead, because each coaxial cable used has its own defined
attenuation. For longer leads coaxial cables with lower attenuation are used
and generally these have a larger cross-section, worse mechanical properties
and are more expensive. When using external antennas we recommend protecting
the radio modem with overvoltage protection on the coaxial cable.

We recommend to use vertical polarization for all radio modem
networks.

Racom radio equipment in typical installations comply with applicable
standards for human exposure to RF electromagnetic fields, namely with
standard EN 50385: 2002. The minimal safe distance is ensured by the antenna
position on a mast. When special installation is required, the conditions of
the standard above have to be met. The distance between the persons and
antenna minimal 5 m comply with applicable standards for human exposure
of general public to RF electromagnetic fields, namely with standard EN
50385: 2002. It is valid for all power levels and all antenna types which
firm Racom provides.

6.3. Power supply

A power supply meeting the specified parameters (see the table of
technical parameters) needs to be used for
supplying radio routers. We recommend using an MS2000 power
supply or other power supply of MORSE
system , which has been developed specially for these purposes, and
where necessary is capable of switching to a back-up battery, as well as
monitoring its state of charge, and also charging.

6.4. Technology connection

The Data Terminal Equipment, a programmable controller, a PC or any
other device communicating over the radio network, has to be connected to
the router by a data cable to the serial or the Ethernet interface according
to the respective standard. These interfaces are described in detail in the
chapter Connectors.

6.5. Mechanical mounting

Radio routers can be mounted either to a mounting plate using screws
or by mounting on a DIN rail. See the table of technical parameters for the
dimensions and spacing separation of mounted parts. Generally for industrial
applications the radio routers are mounted together with the
overvoltage protection, power supply, and back-up battery into a switchboard
with IP54 protection.